Stabilising apparatus for ships



March 17, 1964 c. c. MITCHELL STABILISING APPARATUS FOR SHIPS FiledMarch 19, 1962 United States Patent 3,125,057 STABILISING APPARATUS FORQHIPS Colin C. Mitchell, Edinburgh, Scotland, assiguor of onefourth toBrown Brothers & Co. Limited, Edinburgh, Scotland, :1 British company;one-fourth to William Denny & Brothers Limited, Dunbarton, Scotland aBritish company; one-fourth to Allegemeine Elektricitats-GesellschaftSchiifbau, Hamburg-Finkenwerder, Germany, a German company; andone-fourth to Deutsche Werft Aktieugesellschaft, Hamburg, Germany, aGerman company Filed Mar. 19, 1962, Ser. No. 180,438 Claims priority,application Great Britain Mar. 22, 1961 3 Claims. (Cl. 114-126) Thisinvention relates to stabilising apparatus for ships.

It is already known to provide apparatus incorporating a stabilising finpivotally mounted about a pivot pin so that it can be swung out of acavity provided therefor and returned into this cavity and which is alsopivotally mounted about an axis which is at right angles to the axisthrough the said pivot pin. It is also known to provide a rotary vanedrive motor having an outer casing to which the fin is fixed and aninner casing surrounding and fixed to a shaft which is held in a supportagainst rotation about its axis and which supports the fin, the outercasing being furnished with vanes projecting radially into the annularspace between the casings, and the inner casing presenting axialpartitions projecting radially outwards into the annular space betweenthe casings, a vane being arranged between every pair of adjacentpartitions.

A rotary vane motor as described is normally constructed with smallclearances and any appreciable relative movement between the inner andthe outer casing would impair seriously the efficient operation of themotor.

It is an object of the present development to provide a construction inwhich lateral movement or deflection of the fin relative to the shaft ordeflection of the shaft itself will not impair the efficiency of therotary vane drive motor.

A stabilising apparatus for a ship according to the present developmentincorporates a rotary vane drive motor for the fin in which the outercasing is coupled to the fin by a resilient coupling which constrainsthe fin to rotate with the casing but otherwise permits relativemovement between the fin and the casing, and the inner casing is coupledto the shaft but spaced therefrom over at least the greater part of itslength.

The fin may present axially projecting pins penetrating a portion of theouter casing, resilient bushes being interposed between the pins and theouter casing. The portion of the outer casing penetrated by the pins maybe constituted by a radially projecting flange or radially projectinglugs.

The inner casing is preferably attached to the shaft at the end of thecasing adjacent to the pivot pin.

A practical embodiment of the invention is illustrated in theaccompanying drawing in which FIG. 1 is a vertical section of astabilizing apparatus, FIG. 2 is a view to a larger scale of theresilient coupling in FIG. 1, and FIG. 3 is a section through the line33 in FIG. 1. In the drawings 1 denotes a non-rotary fin shaft held atone end in a support constituted by a socket 2 presenting pins 2Aengaging fixed bearings 3 so that the fin shaft 1 is able to swing in aplane normal to the axis of the pins 2A. 4 denotes a fin mounted onbearings 5 and 6 on the shaft 1 so that the fin is rotatable about theshaft 1. 7 denotes the outer casing of a vane drive motor havinginwardly projecting vanes 7A, said outer casing presenting lugs Scarrying resilient bushes 9 penetrated by pins 10 fixed to the fin 4,and 11 denotes the inner casing of the ice vane drive motor through thecentre of which the shaft 1 passes, said inner casing being furnishedwith partitions 11A projecting radially upwards between the vanes 7Ainto the annular space 7B between the casings 7 and 11. The casing 11 isspaced from the fin shaft 1 for the greater part of its length, being incontact with the fin shaft 1 only at the position 12 for the purpose offacilitating centering of the vane drive motor on the fin shaft 1, andis coupled to the fin shaft 1 by way of a coupling 13 consisting of twoflanges 13A connected by bolts 13B and the socket 2. 14 denotes a dustand grit-excluding casing fixed to the fin 4 and engaging the socket 2by way of a gland 15. 16 denotes a sleeve of low-friction materialinterposed between the casings 7 and 11 and 17 denotes packing toprevent escape of operating fluid from the space between the casings 7and 11. 18 and 19 denote annular grooves in the inner casing 11, saidgrooves 18 and 19 communicating with the annular space 7B on oppositesides of the partitions 11A and being connected to respective passages20 and 21 through which operating fluid is to be fed to, or conductedfrom, the grooves 18 and 19 whereby to cause the vanes 7A and thus theouter casing 7 of the connected fin 4 to perform a partial rotation inthe desired direction.

In practice, the fin is moved into an operative position by swinging theshaft 1 about the pivot pins 2A to cause the fin to move outwardly fromthe cavity provided therefor. The fin is swung about the shaft byadmitting fluid under pressure to the appropriate spaces between thevanes 7A, and the partitions 11A in the rotary vane motor 7, 11, thepressure in these compartments acting between the partitions 11A on theinner casing 11 which is held stationary by its connection with theshaft 1 by way of the coupling 13, and the vanes 7A on the outer casing7 coupled to the fin 4 being effective to cause the outer casing 7 torotate relatively to the inner casing 11 and to carry the fin 4 alongwith it. The fin 4 must consequently always follow the outer casing 7and perform identical rotational movements. During operation of the finlateral movement or deflection of the fin 4 relative to the shaft 1 isabsorbed by the resilient coupling provided between the fin and theouter casing and constituted by the pins 10 and the resilient bushes 9,and deflection of the shaft 1 has a negligible effect on the innercasing 11 since the inner casing 11 is spaced from the shaft 1 over thegreater part of its length and is in contact with the shaft 1 only atthe point 12 close to the point where the shaft 1 is held in its socket.At the point 12 any normal deflection of the shaft 1 is less than thenormal working clearances in the vane drive motor 7, 11. The operationof the rotary vane motor is thus not impaired by any lateral movement ordeflection of the fin 4 or the shaft 1. The inner casing 11 is incontact with the shaft 1 at the point 12 to facilitate aligning of theaxes of the vane drive motor and of the shaft 1.

What is claimed is:

1. A stabilizing apparatus for a ship incorporating a support, anon-rotary shaft engaged at one end with the support, a fin rotatableabout the shaft, and a rotary vane drive motor having an inner casingsurrounding the shaft and coupled to the shaft but radially spaced fromthe shaft over at least the greater part of its length, an outer casing,a flexible coupling connecting the outer casing to the fin in suchwiseas to constrain the fin to rotate with the casing but otherwise topermit relative lateral movement between the fin and the casing, vanespresented by the outer casing projecting radially into the annular spacebetween the casings, and radial partitions projecting from the innercasing into the annular space between the casings, each vane beingbetween two adjacent partitions, and means for conducting operatingfluid to and from the annular space between the casings.

2. Apparatus as claimed in claim 1 in which the resilient couplingincludes axially projecting pins penetrating a portion of the outercasing, resilient bushes being interposed between the pins and theportion of the outer casing.

3. Apparatus as claimed in claim 1 in which the inner casing of the vanedrive motor is in contact with the shaft only at the end of the casingadjacent to the shaft support.

4 References Cited in the tile of this patent UNITED STATES PATENTS2,210,935 Giliberty Aug. 13, 1940 2,848,971 Kollenberger Aug. 28, 19583,036,540 Gregor May 29, 1962 FOREIGN PATENTS 825,134 Great Britain Dec.9, 1959

1. A STABILIZING APPARATUS FOR A SHIP INCORPORATING A SUPPORT, ANON-ROTARY SHAFT ENGAGED AT ONE END WITH THE SUPPORT, A FIN ROTATABLEABOUT THE SHAFT, AND A ROTARY VANE DRIVE MOTOR HAVING AN INNER CASINGSURROUNDING THE SHAFT AND COUPLED TO THE SHAFT BUT RADIALLY SPACED FROMTHE SHAFT OVER AT LEAST THE GREATER PART OF ITS LENGTH, AN OUTER CASING,A FLEXIBLE COUPLING CONNECTING THE OUTER CASING TO THE FIN IN SUCHWISEAS TO CONSTRAIN THE FIN TO ROTATE WITH THE CASING BUT OTHERWISE TOPERMIT RELATIVE LATERAL MOVEMENT BETWEEN THE FIN AND THE CASING, VANESPRESENTED BY THE OUTER CASING PROJECTING RADIALLY INTO THE ANNULAR SPACEBETWEEN THE CASINGS, AND RADIAL PARTITIONS PROJECTING FROM THE INNERCASING INTO THE ANNULAR SPACE BETWEEN THE CASINGS, EACH VANE BEINGBETWEEN TWO ADJACENT PARTITIONS, AND MEANS FOR CONDUCTING OPERATINGFLUID TO AND FROM THE ANNULAR SPACE BETWEEN THE CASINGS.